Source/JavaScriptCore/runtime/WriteBarrierInlines.h

/*
 * Copyright (C) 2014-2021 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
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#pragma once

#include "VM.h"
#include "WriteBarrier.h"

namespace JSC {

template <typename T, typename Traits>
inline void WriteBarrierBase<T, Traits>::set(VM& vm, const JSCell* owner, T* value)
{
    ASSERT(value);
    ASSERT(!Options::useConcurrentJIT() || !isCompilationThread());
    validateCell(value);
    setEarlyValue(vm, owner, value);
}

template <typename T, typename Traits>
inline void WriteBarrierBase<T, Traits>::setMayBeNull(VM& vm, const JSCell* owner, T* value)
{
    if (value)
        validateCell(value);
    setEarlyValue(vm, owner, value);
}

template <typename T, typename Traits>
inline void WriteBarrierBase<T, Traits>::setEarlyValue(VM& vm, const JSCell* owner, T* value)
{
    Traits::exchange(this->m_cell, value);
    vm.writeBarrier(owner, static_cast<JSCell*>(value));
}

inline void WriteBarrierBase<Unknown, RawValueTraits<Unknown>>::set(VM& vm, const JSCell* owner, JSValue value)
{
    ASSERT(!Options::useConcurrentJIT() || !isCompilationThread());
    m_value = JSValue::encode(value);
    vm.writeBarrier(owner, value);
}

inline void WriteBarrierStructureID::set(VM& vm, const JSCell* owner, Structure* value)
{
    ASSERT(value);
    ASSERT(!Options::useConcurrentJIT() || !isCompilationThread());
    validateCell(reinterpret_cast<JSCell*>(value));
    setEarlyValue(vm, owner, value);
}

inline void WriteBarrierStructureID::setMayBeNull(VM& vm, const JSCell* owner, Structure* value)
{
    if (value)
        validateCell(reinterpret_cast<JSCell*>(value));
    setEarlyValue(vm, owner, value);
}

inline void WriteBarrierStructureID::setEarlyValue(VM& vm, const JSCell* owner, Structure* value)
{
    if (!value) {
        m_structureID = { };
        return;
    }
    m_structureID = StructureID::encode(value);
    vm.writeBarrier(owner, reinterpret_cast<JSCell*>(value));
}

} // namespace JSC